1. Field of the Invention
The present invention relates to a caulking gun, and more particularly to a caulking gun having an angle adjustment function.
2. Description of the Related Art
A conventional caulking gun in accordance with the prior art shown in FIGS. 7 and 8 comprises a gun body 70 having a first end formed with a mounting hole 73 and a second end formed with a handle 71, a push rod 80 movably mounted on the gun body 70 and extended through the mounting hole 73 of the gun body 70, a push plate 91 mounted on the push rod 80 in an inclined manner and having a first end formed with a locking hole 92 rested on the push rod 80, an elastic member 90 mounted on the push rod 80 and biased between the gun body 70 and the push plate 91, a trigger 72 pivotally mounted on the gun body 70 and having an end rested on a second end 93 of the push plate 91 to push the push plate 91 to move, a barrel 74 mounted on a side of the gun body 70 and having an inside formed with a receiving chamber, a pull knob 81 mounted on a first end of the push rod 80, a catch plate (not shown) mounted on a second end of the push rod 80 and movably mounted in the receiving chamber of the barrel 74, and a cartridge (not shown) containing silicone received in the receiving chamber of the barrel 74 and rested on the catch plate.
In operation, when the trigger 72 is pressed, the end of the trigger 72 is urged on the second end 93 of the push plate 91 to push the push plate 91 to move forward in an inclined manner. Thus, the locking hole 92 of the push plate 91 is locked on the push rod 80 in a tilt manner to move the push rod 80 which moves the catch plate to compress the cartridge. After the trigger 72 is released, the push plate 91 is pushed by the restoring force of the elastic member 90 to move backward in a horizontal manner without moving the push rod 80. Thus, the push rod 80 and the catch plate are moved forward successively by pressing the trigger 72 repeatedly to compress the cartridge so as to squeeze the silicone outward from the cartridge for use.
However, when the locking hole 92 of the push plate 90 is worn out during a long-term utilization, the diameter of the locking hole 92 of the push plate 90 is enlarged to form a worn portion 94, so that the locking hole 92 of the push plate 91 cannot lock the push rod 80 to move the push rod 80. Thus, the conventional caulking gun cannot be used when the locking hole 92 of the push plate 91 is worn out, thereby decreasing the lifetime of the conventional caulking gun.